1. Field of the Invention
The present invention relates to a method of describing the features of compressed or uncompressed audio data and a method of constructing the feature description collection of compressed or uncompressed audio video data. The audio feature description method is a method of describing an audio feature attached to audio data and enables high-speed, efficiently search and browse audio data at various levels from coarse levels to fine levels. Also, the audio video feature description collection construction method is a method of collecting the feature descriptions of multiple items of audio video data according to a specific feature type, and constructing multiple feature descriptions conforming to the specific feature type as a feature description collection, thereby making it possible to acquire a feature description collection based on the specific feature type from multiple audio video programs.
2. Description of the Related Art
The description of the features of audio data can represent the features of the entire audio data with a small quantity of features by describing or combining the spatial features or frequency features of an audio file existing as a compressed or uncompressed file. The feature description can be employed as an element for grasping the summary of audio data when searching the audio data. The feature description is effective when searching desired audio data from an audio database and browsing the content of the desired audio data.
Conventionally, methods of describing features have been considered mainly for video information. The considerations have been, however, only given to how to represent feature values for audio data. How to combine which feature values so as to describe entire audio data has not been specified or considered yet.
Meanwhile, the description of the features of audio video data has been currently studied at MPEG-7 (Motion Picture Coding Experts Group Phase 7) in ISO (International Organization for Standard). In the MPEG-7, the standardization of content descriptions and description definition languages for allowing efficient search to compressed or uncompressed audio video data is now underway.
In the MPEG-7, feature descriptions from various viewpoints are standardized. Among the feature descriptions, a summary description allowing high-speed, efficient browsing of audio video data is allowed to describe only information for a single audio video in the MPEG-7. As a result of this, summary information according to various summary types on a single audio video program can be constructed and described. Summary types involve important events of the program, important audio clips, video clips and so on.
For example, as shown in FIG. 22A and 22B, for single audio video programs 50 and 51, i.e., complete audio video programs 50 and 51, summary information on various summary types, e.g., “home run”, “scoring scene”, “base stealing scene” and “strike-out scene”, can be described as a summary collection.
As for a summary description, for example, among conventional features descriptions of audio video data, summary information only for a single video audio program can be constructed and described as shown above. However, the construction and description of summary information for multiple audio video programs are not currently specified.
Further, if a feature description collection is described using the feature descriptions of a summary collection from multiple programs in a currently specified framework, e.g., if a feature description collection is described using the feature descriptions of a summary collection from, for example, multiple programs 50, 51, as shown in FIGS. 22A or 22B, then the feature description collection is expected to be described as shown in, for example, FIG. 15A. Namely, it is expected that summary information on the summary collection for each program are simply collected and described.
Consequently, the conventional feature description collection tends to be redundant and unnecessary processings are carried out to search a desired summary from the summary collection, making disadvantageously search time longer. Further, it is difficult to clearly describe the designations of programs to be referred to for each summary. Besides, in case of searching a desired summary from the summary collection, it is difficult to represent a combination of multiple summary types.